The committee McCarthy chaired at the time of his notorious anti-Communist crusade was the Senate Permanent Subcommittee on Investigations, which still exists.

You may be thinking of the House Un-American Activities Committee, which also spent some time doing similar anti-Communist witch hunts, which existed until being renamed as the House Internal Security Committee in 1969, and was abolished with it's functions transferred to the House Judiciary Committee in 1975.

Thanks. So it boils down to China being where USA was 50 years ago, freedom of speech-wise?

Well, no, 63 years ago was Yates v. US; even through the height of the anti-Communist witch hunting phase, the US had a stronger protection of free speech rights of Communists than China has for dissidents today.

https://en.m.wikipedia.org/wiki/Yates_v._United_States